This invention relates to methods of producing intraocular lenses (IOLs), in particular to methods for producing IOLs structured to be repositioned after being placed in an eye.
The vision impairing disease, known as cataract, can be alleviated by surgically replacing the natural lens of the eye with an artificial IOL. Such an IOL may be inserted in the eye by a variety of well known surgical procedures. However, once the IOL is placed in the eye, it is often found that the IOL optic is or becomes decentered or otherwise moves to a less-than-optimal position in the eye.
IOLs, for example, IOLs located in the anterior chamber or posterior chamber of the eye, which are not optimally positioned in the eye or centered on the visual axis of the eye are prone to a variety of optical and physical problems, such as optical distortion, edge glare, second images, reduction in multifocal effect (in some designs) and the like. In addition, posterior chamber opacification may be altered or encouraged by a decentered IOL. Decentration has been reduced by use of continuous capsulorhexis techniques and bag placement, but has not been eliminated. Further, the smaller diameter IOL optics increasingly used today tend to require more precise positioning and to be more sensitive to relatively minor amounts of mal-positioning than their larger diameter predecessors. Even a perfectly positioned IOL may move slightly as remnant lens epithelial cells fill in the capsule.
Repositioning an IOL by mechanical means after IOL implantation is an invasive procedure involving reopening the eye and working behind the iris. In extreme cases, IOL removal may be indicated. Aside from the disadvantages of the surgical procedure itself, possible further complications include inflammation, infection, pigmentary dispersion and endothelial damage.
It would be advantageous to provide methods for producing IOLs that can be repositioned after being placed in the eye without requiring such invasive surgical techniques.